Modeling Methodology Of Milling Deflection And Flexible Milling Force For Tooth Profile Of Low-rigidity Cycloid Gear In High Speed Milling

To resolve the problem of high accuracy profile for thin-wall component with complex profile during high speed milling process,a model for predicting tooth profile deflection and the flexible milling force model for low-rigidity component with cycloid gear profile is presented to solve the problem of controlling the machined quality in high speed milling. In this model, the key to controlling the machined quality lies in predicting tooth profile deflection for low-rigidity cycloid gear tooth rim. And it provides a theory basis for flexible cutting forces. The achievements of research provide significant in theory for the controlling the machined quality in high speed milling thin-wall component. And the modeling method and the conclusions have important significance in increasing the whole level of Manufacture and meeting the China key business.A milling deflection model for predicting the bending-torsional coupled deflection based on low-rigidity cycloid tooth profile, to determine the relationship between deflection and milling force is approached. In the model a differential equation that describes the coupled deflection of the cutting immersed area on the low-rigidity cycloid tooth profile is provided. And a method is provided to identify the key processing characteristics of the coupled deflection which involves the bending deflection, torsional deflection and shearing deflection. According to the construction of the statically indeterminate low-rigidity tooth rim fixed two ends the supporting forces and deflections under the action of applied forces on the end are derived on Casfigliano's Second Theorem.Assuming the slender cutter as a Timoshenko beam consisting of the shank and the flute the cutter bending deflection is derived. In the bending deflection model, take into account the effects on the inertia of the cutter edges. In this paper, tool runout is presented. The method can be used to express the centre coordinates of tool due to the cutter runout.A flexible force model suitable for cycloid gear profile is proposed based on the milling deflection in the workpiece-tool process. Taking into account the deflections of workpiece and cutter the expressions are derived for process geometries parameters in peripheral milling where curvature varies continuously along the tool path. Then modified cutting tooth immersion angle and undeformed chip thickness have been introduced due to the deflections and process geometries. In machining workpiece geometries, the milling force distribution, deflections of the gear rim and tool for are solved interatively by the modified Newton-Raphson method. According to the measured forces and deflections the results have shown good convergence between predicted and measured values.From the present study it has shown that the cutting tooth immersion angle and undeformed chip thickness subject to the deflectons and process geometries parameters. These will influence the flexible force model. The study has shown that any of the values of the gear stiffness, disk dimension, angle responding to the thin-wall rim, tooth construction and rim dimension has a strongly effect on the milling deflection. It can be shown that the disk width of rim is shared with the cutting force much more than the rim width. When high speed mills the precision cycloid gear profile the deflections of the low-rigidity workpiece and slender tool bring about a great effect on the dimension stability of the finished parts. This is attributed to the complex relation between the milling force and the milling deflection, which will influence the precision of the part.